Kanchan

Revision as of 01:12, 12 June 2024 by Hordes (talk | contribs) (resort again)

Kanchan 「嵌張」 is a wait pattern that completes with the middle number of a sequence.

Kanchan
Kanji 嵌張
English Closed wait, Middle wait
Fu 2 fu
Tile types waiting 1 sided wait
Tiles available 4 tiles
Pattern example
Tenhou.net example Kanchan

Pattern

             

Fu

Kanchan is awarded 2 fu upon winning. A closed hand winning by ron automatically becomes mangan, if it scores 4 han.

Ryankan

A ryankan ("double closed wait") is an extended form of a kanchan, only available before reaching tenpai. A ryankan shape is composed of three tiles that are each 2 apart, such as:

Pattern            
Tiles to complete         

A ryankan is effectively the same as having 2 different kanchans; it waits for 8 tiles of two types (4 tiles per type).

However, you cannot enter tenpai with a ryankan. If you would reach tenpai without completing the ryankan, you'd have to discard one of its three tiles, turning it back into a weak kanchan wait.

Example hand with ryankan shape:

             

With the example hand above, if you drew  , you would have to discard either   or   to enter tenpai. You end up with a bad wait, but with one major advantage - a ryankan always forms a suji trap. Here, if you discarded the 6s, you would wait on the suji 3s, thus making it more likely for others to deal in. This is why a suji of the riichi declaration tile is considered more dangerous.

Strategy

Kanchan is considered to be a "bad wait", because it can only wait for a maximum of 4 tiles. Thus, they are worse for hand development. Like the other bad waits, kanchan can be used to suji trap opponents.

In general, inner kanchans > outer kanchans > penchans when it comes to tile efficiency. See below for details.

Inner vs Outer Kanchan

There are two different types of kanchan: inner and outer.

Type Tiles
Inner         
Outer            

Inner kanchans are generally superior to outer kanchans because they are easier to upgrade.

  • A    kanchan can be upgraded by drawing   (turning into   ) OR   (turning into   ). It can also be turned into a ryankan when drawing either   or  .
  • A    kanchan can only be upgraded by drawing  . It can be turned into a ryankan when drawing   only.

An inner kanchan can be upgraded by twice the amount of tiles, so inner kanchans are overall stronger. Note that an inner kanchan waits on a middle tile. Middle tiles are harder to win with; an inner kanchan is worse to keep at tenpai than an outer one.

Kanchan vs Penchan

While kanchan and penchan wait on the same number of tiles, a kanchan is considered better to keep, because a kanchan has more upgrades. This is similar to how inner kanchans are better than outer kanchans.

  • A    kanchan can be upgraded by drawing  , turning it into a    (two-sided) ryanmen.
  • A    penchan cannot be upgraded to ryanmen on its own. It must first draw a  , turning it into a    kanchan, then draw the   to get a ryanmen.

As a kanchan requires 1 drawn tile to be upgraded to a ryanmen, but a penchan requires 2 drawn tiles, the kanchan is superior to keep before tenpai. In addition, only a kanchan can be turned into a ryankan shape, adding another advantage. However, once you reach tenpai, both kanchan and penchan become effectively identical.

External links